Field of the Invention
The present disclosure relates to a semiconductor device and particularly to a fuse element.
Description of the Background Art
Conventionally, a semiconductor integrated circuit commonly includes a circuit for adjusting a resistance value, which is referred to as a resistor trimming circuit, in order that resistance values of a polysilicon resistance and the like incorporated in the wafer process can be adjusted in the subsequent process. Among others, a laser trimming fuse is configured such that a desired fuse element can be separated using a laser beam, which is a technique used for a semiconductor integrated circuit requiring a large number of fuses.
A vertically-structured power device (for example, an IGBT (Insulated Gate Bipolar Transistor)) serves to sense the temperature information of a power device based on the VF characteristics of the temperature sensing diode incorporated in the power device, thereby performing a function of protecting the IGBT element from heating (a heating protection function). The temperature sensing diode formed of a power device cannot however be formed on an Si substrate, and therefore, is formed of a polysilicon layer on an oxide film formed on the Si substrate. This leads to problems that VF characteristics greatly vary, so that the temperature cannot be sensed with high accuracy.
The present invention provides a function of correcting such variations in temperature sensing diode characteristics, thereby improving the temperature sensing accuracy. For this purpose, for example, a trimming element for sensing the information on the temperature sensing diode is provided, for which various methods such as a trimming method by laser cutting are proposed.